Microparticle filter



FIG. 1 is a front view of our new design for a microparticle filter;

FIG. 2 is a left side view thereof;

FIG. 3 is a right side view thereof;

FIG. 4 is a plan view thereof;

FIG. 5 is a bottom view thereof; and,

FIG. 6 is a cross-section view of the microparticle filter shown in FIG. 4 taken along a line A—A' shown in FIG. 4. 

The ornamental design for a microparticle filter, as shown and described. 